If a pulse wave traveled for 125 meters and took 8 seconds, what is the speed or velocity of the pulse wave?

Heterogeneous mixture with larger particles that never settle is

In a game of pool, ball a is moving with a velocity v0 of magnitude v0 = 15 ft/s when it strikes balls b and c, which are at rest and aligned as shown. knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (that is, conservation of energy), determine the magnitudes of the velocities va, vb, and vc.

If a 250-g mass is hung on two identical springs, hung side by side , and both support the 250-g mass, how much will each spring stretch?